Clutch or brake mechanism.



' JOHN LAIDLAW AND JAMES WRIGHT MAGFARLANE, or GLAsGoW, SCOTLAND.

. CLUTCH on BRAKEYMECHANISM.

Specification of Letters Patent. W Application filed May 22, 1905. Serial No. 261,693.

Patented J' an. 1, 19'07.

' To all whom it may concern..-

Be it known that we, JOHN LAIDLAW and JAMEs WRIGHT MA'OFARLANE, subjects of the King of Great Britain and Ireland, and residents of Glasgow, Scotland, (whose postal address is 98 Dundas street, Kingston, Glasgow, Scotland,) have invented certain new and useful Improvements in and Connected 'With Clutch or Brake. Mechanism for Centrifugal Machines, of which the'following is a specification.

clutch andbrake can ,only be put into oper- Hitherto when centrifugal machines have been driven by electric motors it has been customary to start and stop'the motor when it was desired to start and stop the machine.

The invention has for its object to provide improved means for operating a clutch applied between two shafts and a brake a ied to one of the shafts, such that t e ation alternately and not simultaneouslythat is to say, if the clutch be in gear the brake must of necessity be off, if the brake sheet of explanatory drawings, showing be on the clutch must be out of gear. Thus risk of damage due to inadvertent putting on of the brake when the clutch is in ear and putting in gear of the clutch when t e brake is on is entirely eliminated.

In order that the invention and the manner of performing the same may be properly understood, there is hereunto appended a 1n sectional elevation the application of the improved clutch and brake operating mechanism to a centrifugal machine.

In the drawings, the improved clutch and brake operating mechanism is shown in combination with the clutch forming the sub- 1 ject-matterof our concurrent a plication for apatent filed March 2, 1906, erial No.

303,847. The electric motor (which is not shown) is carried upon a stool 25, which is formed as an extension of the usual housing 26, carrying the/jbasket-carrying spindle 8, by means of'a conoidal bufi'er 27 of known type, which engages the outer conical surface of the bearing 28 of that spindle, the whole being shown as-carried u on beams 29.":-

.The stirrup ring 5 of t e clutch is operated by a bifurcated stirrup-lever 30, centered upon. a'stud 3-1 in the lower part of the motor 25, and, engaging "trunnion-pins 32, formed upon the ring 5. This lever 30 extends laterally outward in a single arm,

made in two parts re a link 33 .(which is tively adjustable-by means of a nut 34, lock-nuts being provided to secure it in position) to a crank 35 on a shaft 36, carried in suitable brackets, one, 37, of which is shown assecured to the beam 29.

The brake, which is of a well-known type usually applied to centrifugal machines, consists of a brake-drum 38, fixed to the spindle S and encircled by a brake-band 39. The brake-band is attached at one end to the bracket 37 by a rod 40, and at the other end is slotted to take the rod 40 and the shaft 36 upon which it rides, and at its extreme outer edge is provided with a bearing-strip 41, while at the side remote from its connecwhich is connected by a tion to the shaft and the rod 40 it is sup-.

I the bearing-strip 41.

A handle (indicated-by dotted lines) is provided for rotating the shaft 36, so as to operate the brake by means of the cam 44 and the clutchby means of'the crank 35.

The crank 35 and the cam 44 are so positioned relatively to each other and to the parts which they operate that in the .posi-.

tion in which the parts are shown neither clutch nor brake is in operation. If, however, the handle 45 be moved to the right, the clutch is thrown into gear through the movement imparted to its stirrup-ring 5 throughthe link 33 and stirrup-lever 30,

while the position of the brake is not altered. If, however, the. handle 45 be moved to the left, the cam 44 immediately encountering the bearing-strip 41 commences to operate the brake,- while at the same time the only effect upon the clutch is to move its members farther apart-that is to say, therefore, that movement of the handle in the one direction operates the clutch to throw itinto gear, the

brake remainin free, while movement in the opposite direction puts onthe brake, the c utch remaining free-and when the parts are in mid position. both clutch and brake are out of operation. Thus'while the motor is running the centrifugal machine may be started by a movementof the handle 45 to the right, and when it is desired to stop the ma- P tently connectin them, a clutch-operating 2o chine (the motor still continuing to rotate) the clutch is freed and the brake put on by a movement of the handle to the left, or while the handle is in mid-position the machine is free to be turned by hand, if required, to facilitate the discharge of its contents. At the same time it is obviously impossible that both brake and clutch be put into operation at the same time.

Clearly the improved clutch and brake operating devices are applicable to brakes and clutches of forms other thanthose referred toherein.

We claim as our invention In combination with a continuously-running shaft, and a second shaft coaxial therewith and intermittently driven therefrom, a clutch between the two shafts for intermitlever, a band-bra e upon the second shaft, a handled operating-shaft, a crank thereon, a link between the crank and the clutch-operating lever, and a cam u on the handled shaft and operating the bra e, the crank and :5 cam being so set relatively to each other and to the parts they operate that clutch and brake can only be engaged alternatively and not simultaneously.

In testimony whereof we have signed our 0 names to this specification in the presence of two subscribing witnesses.

JOHN LAIDLAW. JAMES WRIGHT MACFARL'ANE.

Witnesses DAVID FERGUSON, URIPED HUNT. 

